1. Field of Invention
This invention relates to device and method for guiding the visually-impaired pedestrian relative to danger-zones such as vehicular crossings proximal paved walkways; and more specifically, it relates to those types of apparatus devised with raised foot-tactile demarcations.
2. Background History
With increased awareness as to the need for improved safety precautions for the estimated 12-million persons having varying degrees of disabling sight impairment, on 26Jul. 1991, the U.S.Congress published federally legislated Regulation—US/CFR-Parts: 35 & 36 (Re: gov.structures & pvt.structures respectively) regarding actual implementation of truncated-domes, which regulation was ushered in by the U.S. Justice Dept. via their truncated-domes, which regulation was ushered in by the U.S. Justice Dept. via their ADA/Americans w/Disabilities Act Dept. (Re: tech.info: www.access-board.gov);-however the Fed.DOT/Dept.-Of-Transportation also has its jurisdiction governing installation of these truncated-comes relative to transit/boarding-platforms, etc. This regulation addresses numerous federal-requirements regarding access to both public-facilities (state & local) and private-facilities, -by the disabled. While the ADA & DOT timetable requirements for govermental facilities to adopt the installation of truncated-domes upon walkways appears as of yet unspecified, the requirement for privately-owned facilities open to the public has been fairly clearly mandated (although subject to refinement owing experience being gained by actual usage). Here, all new/private-buildings considered generally accessable by the public, were, effective 26 Jan. 1993, required to comply with the ADA-regulation defining specific installation as to the physical configuration of foot-tactile detectable-warning means. The Federal-specifications mandated the size of truncated-dome formations to be provided upon the walking-surface of street curb-ramps and a walking-surface proximal a vehicular-way or other danger-zone (ie: reflecting-pool, or boarding-platform) not otherwise separated by a curb or railing. Detectable-warning means for paved-walkways are generally defined as: “a standardized integral surface built-in or overlaid in a permanent manner, and are presently to be finished in a mono-chromatic color (ie:—yellow) that would contrast with adjacent walkway surfacing. Moreover, the truncated-dome (TD) entities are presently decreed to have a nominal 0.90″-1.40″ diameter (at base), nominal 0.20″/height (above base), and nominal 0.45″/flat-top portion, plus center-to-center 1.67″/interval-spacing (hence a 2.35″/interval-spacing measuring diagonally between rows of TD's),—which therefore equates to a 7×7 TD-matrix format within a given conventional 12″×12″-square paving-tile for example; and Installation of the TD/paving-tiles are thus formatted in walkway-widths of 24″, 36″, or 48″. Note that while not exempting the novel TD configuration being introduced by this instant disclosure, the Federal-regulations actually had no anticipation of my novel embodiment;—owing that heretofore the TD's only were known to be molded integrally with rubber-like paving-tiles, cast integrally as nodules extending above a cementous surface, or applied in the form of a moltant catalyzed-resin which would harden in-place upon a walkway (this last iteration being applied as, blobs of epoxy basically,—therefore not accurately meeting the Fed.—requirements dimensionally).
3. Relevant Prior-Art
Research discovery provides some prior patent-art regarded as germane to this disclosure, chronologically for example U.S. Pat. No. 1,469,146 (filed: August 1922 issued to L. J. Betts) is shown a motor-vehicle traffic-marker device which is truncated in formation, thereby presenting a dome like face whilst its substantially planar bottom-side includes means by which the device is mechanically bolted to the street surface. Other similar such improved devices were subsequently patented, whereupon in the late 1940's a CalTrans/R&D-technician Elbert D. Botts invented (although never patented) a durable night and rain visible white-ceramic approximately 3½-inch diameter truncated-dome device which was installed as non-intrusive median-markrs down the center of California's highways. At speed, these devices would interact with the vehicle's tire in such a way as to generate an alarming vibration that would both audibly and vibrationally alert the perhaps drowsy motorist that they had better move their dangerously drifting vehicle back into their proper lane of travel. However, median streams of these early RPM's (reflective pavement markers) as Botts called them, were retained into the road-surface via an integral-spike which proved to be impractical in as much as once they had worked loose over time from tire-impacts,—they became terrible road hazards in of themselves. In the early 1950's a viable solution to this installation calamity was posed by H. Rooney an understudy of Botts,—which was to simply affix the Dot devices with a tough new cementing-agent Epoxy-resin (this notion was never patented either). Thus CalTrans evaluation resumed during the 1950's, unfortunately Dr. Botts (Phd.-Chemistry) died before he could see the popular implementation of their utterly simple albeit exceptionally effective road-safety idea which has indeed saved millons of lives,—yet he is honored today by their being appreciatively referred to as “Botts Dots”!
Then in U.S. Pat. No. 1,647,861 (filed: June 1925) is shown a Street-button made of stamped-steel, having four downwardly projecting integrally formed legs which are driven into the asphaltum or yet uncured cementous street-surface for positive retention. Although no mention was set forth as to the notion of foot-tactility detectable to the blind, to negate a pedestrian slipping thereon, the exposed top-surface of the Street-button was substantially flush with the pavement-top, and included a matrix of nine tiny embossed convex nodules which projected upward about ⅛-inch. The devices were intended to be installed along the existing painted white-stripping used to delineate pedestrian/cross-walks; and as such, were considered by the inventor to be more durable and lasting as compared to painted-demarcations.
Later in U.S. Pat. No. 4,715,743 (filed: June 1986) and in U.S. Pat. No. 5,303,669 (field: September 1992) is shown an abutted array of flexile tile panels composed of a generally yellow-colored synthetic-rubber like material upon which upwardly facing side is integrally-molded a plurality of foot-tactile truncated nodules functioning as detectable-warning elements capable of assisting the visually-handicapped to know they are proximal a hazardous zone where vehicles travel, or are traversing a trolly/loading-platform for example. However, these tiles have a thickness requiring they be installed into a planar-recess, and recent studies have shown these tiles can in of themselves pose a potentially serious tripping hazard to all pedestrians as the tiles become aged;—whereby their perimeter-edges sometimes protrude upward from their normally flush-mounted condition, whereupon a person can stub the toe of their shoe and suddenly stumble to an injurious fall.
Next, in U.S. Pat. No. 5,271,690 (filed: February 1992) and U.S. Pat. No. 5,320,790 (filed: July 1992) are set forth similar methods for producing a durable foot-tactile detectable-warning surface, and as such, contemplate a female-embossed pattern means by which to overlay an existing pavement-surface with plural detectable-warning nodules,—or otherwise like impressions cast into the top surface of a completely new sidewalk for example. Accordingly, the resulting tactlized surface is thus all integrally formed with the spaced apart nodules, which is durable, yet is generally rather costly owing that an existing sidewalk area to have the requisite detectable-warning surface would usually have to be entirely replaced in order that the final new surface remain flush with the adjoining sidewalk surfaces.
In pending U.S. Pat. No. 2003/0037720 (filed: August 2002) is shown a detectable-warning and directional-guidance apparatus and method, in the form of uniformly spaced apart elongate ABS-plastic (ie: Fed.DOT-approved Centrex®—brand) marker elements arranged in parallel groups bonded to the existing pavement by epoxy-adhesive (ie: Fed.-DOT approved EAS-6);—the notion being to thereby orient a visually-impaired pedestrian to proceed in the azimuth direction referenced by the linearity of the 24-inch long×1-inch wide strips. Recent findings by the U.S. Accessibiiities Board indicates that this particular elongated form of detectable-warning device has failed to function well with the special Blind-cane which emits a sonar like signal that is monitored by the blind user.
Therefore, in full consideration of the preceding patent review, there is determined a need for an improved form of device to which these patents have been largely addressed. The instant inventor hereof believes their newly improved pavement safety device, commercially referred to as D.W.DOTS™, currently being developed for production under auspices of the AmBrit-Mfg./Mkt.-LLC (website: “www.dwdots.com”) exhibits certain advantages as shall be revealed in the subsequent portion of this instant disclosure.